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71.
While most BK virus infections are asymptomatic, immunosuppression has been associated with BK virus reactivation and impaired graft function or ureteric ulceration in renal transplant patients and hemorrhagic cystitis in bone marrow transplant patients. Oncogenicity is also postulated and this is the first report of a child with a carcinoma of the donor renal pelvis following BK virus allograft nephropathy. Removal of the primary tumor and cessation of immunosuppression led to regression of secondary tumors and a return to health.  相似文献   
72.
HYPOTHESIS: Younger patients with immune thrombocytopenic purpura (ITP) and high preoperative platelet counts successfully respond to laparoscopic splenectomy (LS). DESIGN: Case series. SETTING: Private, tertiary care referral center. PATIENTS: Sixty-seven consecutive patients undergoing LS for ITP between 1995 and 2001. INTERVENTIONS: Laparoscopic splenectomy. MAIN OUTCOME MEASURES: A successful response to LS was defined as a postoperative platelet count greater than 100 x 10(3)/microL without medical therapy. Failures were classified as recurrent or refractory. Patients considered refractory to surgery did not achieve a platelet count greater than 100 x 10(3)/microL without medical therapy. Patients with recurrent ITP initially achieved a platelet count greater than 100 x 10(3)/microL, but thrombocytopenia subsequently recurred. RESULTS: Both univariate and multivariate analyses were performed for 13 preoperative variables to identify factors predictive of success following LS. At a mean follow up of 22 months, 43 patients (64%) had a successful response to LS, 14 (21%) were refractory, and 10 (15%) developed recurrent ITP. By univariate analysis, patients responding to laparoscopic splenectomy were younger (P =.005) and had a higher preoperative platelet count (P =.005). In multivariate analysis, younger age (P =.005) and a higher preoperative platelet count (P =.007) again predicted a successful response to LS. CONCLUSIONS: A successful response to LS for ITP is expected in patients younger than 50 years and in those with preoperative platelet counts greater than 70 x 10(3)/microL. These factors can be incorporated into an equation that yields a splenectomy prediction score, which predicts the success of LS for ITP.  相似文献   
73.
Sehba FA  Chereshnev I  Maayani S  Friedrich V  Bederson JB 《Neurosurgery》2004,55(3):671-7; discussion 677-8
OBJECTIVE: Subarachnoid hemorrhage (SAH) is associated with acute decreases and subsequent recovery of cerebral nitric oxide (NO) levels, but the mechanisms of these alterations are not known. In this study, we measured NO synthase (NOS) protein and kinetics to determine its involvement in the alterations of cerebral NO levels after SAH. METHODS: The endovascular rat model of SAH was used. The number of NOS-1 (neuronal) and NOS-2 (inducible)-positive cells (0-96 h) was determined by counting immunoreactive cells in 8-microm cryostat sections. The tissue content of active NOS and its kinetic parameters were studied with an enzymatic l-citrulline assay. RESULTS: The number of NOS-1-positive cells increased between 1 and 3 hours after SAH, decreased to and below control values at 6 and 72 hours after SAH, and increased to control values 96 hours after SAH. The number of NOS-2-positive cells increased 1 hour after SAH, decreased to control values at 24 hours, and increased above control values 96 hours after SAH. The Michaelis-Menten kinetic parameters (V(max), K(m), slope) of NOS remained unchanged at 10 and 90 minutes after SAH. CONCLUSION: NOS-1 and -2 proteins undergo a triphasic alteration after SAH, whereas the amount of active NOS and its kinetic parameters remain unchanged during the first 90 minutes after SAH. Depletion of NOS is not involved in the acute alterations of cerebral NO levels after SAH.  相似文献   
74.
BACKGROUND: Body dysmorphic disorder is a relatively common condition in patients seeking elective surgery. Little has been written, however, in the dermatologic surgery literature about body dysmorphic disorder, where proper recognition and management of this disorder is needed during this time of increased demand for aesthetic dermatologic surgery. OBJECTIVE: The objective was to review the prevalence, demographics, clinical features, treatment approaches, and referral suggestions for patients with body dysmorphic disorder in an attempt to facilitate care of such patients in a general dermatologic surgical practice. METHODS: We reviewed the dermatologic, cosmetic surgical, and psychiatric literature regarding body dysmorphic disorder and related disorders. RESULTS: Body dysmorphic disorder is observed in 6% to 15% of dermatologic and cosmetic surgery patients and in 2% of the general population. Surgical treatment of patients with body dysmorphic disorder typically leads to no change or worsening of symptoms in the majority of patients. The use of screening questionnaires and observation for hallmark features are helpful for clinicians in managing patients with body dysmorphic disorder. Psychiatric referral is desirable, because cognitive behavioral therapy and pharmacologic intervention with selective serotonin reuptake inhibitors are often efficacious. CONCLUSIONS: Body dysmorphic disorder is often underdiagnosed and suboptimal management is common. Effective treatment consists of behavioral and pharmacologic intervention. Use of the Dufresne Body Dysmorphic Disorder Questionnaire appears to be useful as a screening tool in an outpatient setting, and awareness of clinical features of body dysmorphic disorder in the dermatologic surgical setting may spare patients significant morbidity while allowing surgical dermatologists to manage their patients and practices more effectively.  相似文献   
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Epidural spinal injections can be administered via a translaminar or transforaminal route, depending on the clinical scenario. When it is more desirable to target a specific nerve root, a transforaminal approach is typically used, and when the target is more diffuse, a translaminar method is chosen. Both are commonly used and can be utilized similarly in the lumbar or cervical spine. However, it is essential that the clinician understand the risks and benefits of these injections. In the lumbar spine, both translaminar epidural steroid injections (TLESI) and transforaminal epidural steroid injections (TFESI) have been shown to provide up to 6 months of pain relief, though long-term benefits are less reliable. In the cervical spine, translaminar injections may provide longer relief and have a lower complication rate than cervical transforaminal injections. Proper technique is essential to minimize the rate of these rare but occasionally severe complications.  相似文献   
77.
Diffusion tensor imaging (DTI) has recently emerged as a useful tool for assessing traumatic brain injury (TBI). In this study, the prognostic value of the relationship between DTI measures and the clinical status of severe TBI patients, both at the time of magnetic resonance imaging (MRI), and their discharge to acute TBI rehabilitation, was assessed. Patients (n=59) admitted to the trauma center with severe closed head injuries were retrospectively evaluated after approval from the institution's institutional review board, to determine the prognostic value of DTI measures. The relationship of DTI measures, including apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial (λ‖) and radial diffusivity (λ⊥) from the whole brain white matter, internal capsule, genu, splenium, and body of the corpus callosum, were compared with neurological status at MRI and at discharge to acute TBI rehabilitation. Whole brain white matter averages of ADC, λ‖, and λ⊥, and their coefficient of variation (CV) were significantly correlated with the Glasgow Coma Scale (GCS) score on the day of MRI. The average λ‖ was significantly correlated with GCS scores on the day of MRI in all measured brain regions. Outcomes were associated with whole brain white matter averages of ADC and λ‖, and the CVs of FA, ADC, λ‖, and λ⊥; and the averages and CVs of FA and λ‖ in all corpus callosum regions. The inclusion of regional and global DTI measures improved the accuracy of prognostic models, when adjusted for admission GCS score and age (p<0.05). Whole brain white matter and regional DTI measures are sensitive markers of TBI, and correlate with neurological status both at MRI and discharge to rehabilitation. The addition of DTI measures adjusted for age, gender, and admission GCS score significantly improved prognostic models.  相似文献   
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Introduction

Gemcitabine is standard treatment for pancreatic cancer but has limited clinical benefit due to chemoresistance. Nuclear factor-kappaB (NF-??B) can promote chemoresistance and is therefore an attractive therapeutic target. We hypothesize that NF-??B suppression with the novel, orally bioavailable inhibitor dimethylamino parthenolide (DMAPT) will sensitize pancreatic cancer cells to gemcitabine.

Methods

BxPC-3, PANC-1, and MIA PaCa-2 human pancreatic cancer cell lines were treated with gemcitabine and/or DMAPT. Effects on the NF-??B pathway were determined by electrophoretic mobility shift assay, ELISA, or Western blot. Proliferation and apoptosis were measured by cell counts and ELISA, respectively. The effect of gemcitabine in vivo was determined using a MIA PaCa-2 heterotopic xenograft model.

Results

Gemcitabine induced NF-??B activity in BxPC-3, PANC-1, and MIA PaCa-2 cells and decreased the level of the NF-??B inhibitor I??B?? in BxPC-3 and PANC-1 cells. DMAPT prevented the gemcitabine-induced activation of NF-??B. The combination of DMAPT/gemcitabine inhibited pancreatic cancer cell growth more than either agent alone. Gemcitabine also induced intratumoral NF-??B activity in vivo.

Conclusions

DMAPT enhanced the anti-proliferative effects of gemcitabine in association with NF-??B suppression in pancreatic cancer cells in vitro. Furthermore, gemcitabine induced NF-??B activity in vivo, thus supporting the evaluation of NF-??B-targeted agents to complement gemcitabine-based therapies.  相似文献   
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